Woodmizer LX55 Electric motor

[Bruno of NH]

Can you run the mill off of a generator till you get the new gas powered mill ?
I have a 5hp table saw I ran on a generator while I waited to get power run to my house site.

[homesteading]

@Billmaz . That's not the way it works around here, god forbid you have an issue or recommend a sawmill outside of the sponsors to the left. Can't pith off the sponsors that allow you to post here, which I was basically told by the admin.

Funny, I thought my ability to post here was actually my doing, you can delete my account and my pictures, that you do not own, no matter what fly by night attorney drew up your agreement.

The members make the community, not the sponsors. You drive a lot of people away with that mentality. Peace out.

[Jeff]

Hmmm. Goodbye homesteading.

FOREVER

[busenitzcww]

I have LT15 wide with a 10 hp electric on it works great even if i start the motor with the clutch engaged. I would agree with Southside and say it's a voltage/feed issue. 6 gauge copper should be overkill for that motor.
I wouldn't give up on the electric option, as it's very handy! I love how much quieter it is plus very minimal maintenance!

[Larry]

I agree a 7HP motor should have no problem starting.  I'm wondering if there is some electronic tweaking on the motor.  Possibly a programmable soft start, or perhaps a 3 phase motor powered by a VFD.

I think electric would be well worth the hassle.  I still think its something simple that an industrial electrician could figure out within a few minutes.  I'm sure WM will stick with you to solve the problem.

[Magicman]

I still think its something simple that an industrial electrician could figure out within a few minutes.

I have always felt that there is/was an undiagnosed electrical feed problem that is only problematic under a load.

[dgdrls]

Can you run the mill off of a generator till you get the new gas powered mill ?
I have a 5hp table saw I ran on a generator while I waited to get power run to my house site.

Bruno has a great test here,  this would eliminate any electric supply question and be a second test for the mill motor.
D

[ladylake]

I have LT15 wide with a 10 hp electric on it works great even if i start the motor with the clutch engaged. I would agree with Southside and say it's a voltage/feed issue. 6 gauge copper should be overkill for that motor.
I wouldn't give up on the electric option, as it's very handy! I love how much quieter it is plus very minimal maintenance!

Is your motor made in Italy like the OP, could be WM switched motors .  I have a 5hp Powermatic planer that was slow starting with a china motor, put some little bit bigger capacitors in it, now it starts instantly.  Steve

[ladylake]

Can you run the mill off of a generator till you get the new gas powered mill ?
I have a 5hp table saw I ran on a generator while I waited to get power run to my house site.

Bruno has a great test here,  this would eliminate any electric supply question and be a second test for the mill motor.
D

  It's going to take a GOOD sized generator to get a 7 or 10 hp started under heavy load.  They might be using 80 to 100 amps to get started.  I've watched silo unloader motors start up with a amp gauge which went way up on starts. Steve

[terrifictimbersllc]

I'd be tempted to bring the mill right over next to the power supply and try a very short run of two or four gauge wire, just as a test, to see how it runs. Rule out voltage drop wire problem maybe.

[Magicman]

It could be a connection on the service entrance. 

[busenitzcww]

I have LT15 wide with a 10 hp electric on it works great even if i start the motor with the clutch engaged. I would agree with Southside and say it's a voltage/feed issue. 6 gauge copper should be overkill for that motor.
I wouldn't give up on the electric option, as it's very handy! I love how much quieter it is plus very minimal maintenance!

Is your motor made in Italy like the OP, could be WM switched motors .  I have a 5hp Powermatic planer that was slow starting with a china motor, put some little bit bigger capacitors in it, now it starts instantly.  Steve

I believe it's a marathon motor which I believe is US made.

[tacks Y]

I agree with Steve, put some capacitors on it.

[crmorse]

So I had ordered this exact same mill before I saw this thread. Last Thursday I get the mill and darn if I don't have exactly the same problem as Billmaz.  Armed with the information in this thread I started diagnosing. 

Input voltage = 247v... CHECK
Breaker rating = 50A... CHECK

During start-up I measured and the results shocked me.
Startup current = 120A !WHOA!
Voltage = 190v ---> HMMM, this didn't surprise me as my mill is on a very long run from the service entrance but given the 120A draw it's not too shocking. More info is needed

Once running full speed (only way I got there was lowering some of the tension on the band)
No load current = 17A
Voltage = 240V
Max current while cutting a 8" silver maple at a fast walking speed = 30A

Now the road to get to the above numbers was much longer** and involved a couple of calls to Woodmizer which I must say they handled with excellence. Their knowledge on this particular mill a bit less so but so far it's working out and they're clearly committed to improving so I won't take anything away from them there.

Now, here's what I'm currently thinking. Everything seems good once it's running full speed and even hitting 30A (30A * 240V = 7.2KW = ~9.6HP) doesn't seem too bad. The saw has plenty of power. So I think the problem is in the start circuit.  Now take this with a whole log of salt because everything I know about AC motor start capacitors I learned from this thread and a couple of Google searches then but I think the start capacitor is vastly undersized.  There are 2 caps on the motor, one for start and one for run, and both are 80uF. According to this page a 5hp should have something in the range of 750uF so I feel pretty sure 80uF is just too small.  I will call Woodmizer in the morning and see what they say and update the group here.

** The road to get here is probably worthy of a separate post but Woodmizer said they are updating their assembly instructions based on my notes so I'll wait to see how that turns out before I pipe up.  The relevant bits here are the mast posts and bandwheels were out of plane which resulted in extra friction and per the current setup instructions you level things out with the blade guides which resulted in even more friction. Once I got everything correctly trued up I saw a 3A drop in no-load current and probably a 1/4 drop in noise so I think this is pretty significant and might be part of what's happening to Billmaz.

[ladylake]

  Sounds like they might have sent these motors out with the wrong size capacitors.  Steve

[Old Greenhorn]

Something I thought I had mentioned earlier here, but now I see that I had not. I had an issue with a 480v 100hp motor on a new machine (water jet cutting 90,000 psi) install years ago. It would blow the breaker every time we started the pump. Called the mfg for help. Turned out we were supposed to have a special breaker in the panel for this and somebody missed the fine print. We had to order the breaker and it took several weeks. The way these breakers work, they allow the high in-rush current for a short period of time to allow the motor to come up to speed and settle down before it will trip. As I recall, the breaker we got had a little pot on it to adjust the time lag and was rated for 100 amps (maybe 125?) at 480v. I think it was around $500.00.
 I am not saying this would solve your problem, but you might want to look into it because it seems once your motor is humming at speed all is good, it's just those initial milliseconds that are the issue. Or am I mis-understanding the issue? Anyway, just a thought. Please consult a real electrician as you move forward, someone with experience in such things. Best of luck to all.

[teakwood]

I would also think the start capacitor is too small.

I converted my mill to electric, 7.5hp 3 Phase motor that runs on single phase with the third leg produced with a capacitor.

As a sawmill is a hard start with all the heavy wheels it need to start turning, band tension,.... i needed 1200uf starter capacitors and a 80uf running capacitor.

https://forestryforum.com/board/index.php?topic=109583.msg1713027#msg1713027

Just to add, if you ones tried electric you won't go back to gas!! it's worth all the money and trouble to make it work

[crmorse]

I ran back out to the mill last night and took pics of all the name data. Thought I'd post the info here for posterity.

CIMA Single Phase Asynchronous Motor
Home | Produzione motori elettrici a progetto, asincroni, monofase e trifase | Cima Motori
Type: 132S/2
Duty: S1
M.Y.: 04-02
Insul.Cl.:F-TROP IP55
CAP.: uF 160
Vc: 450
kW: 5.5
Hp: 7.5
Poles: 2
V: 220
A: 33.0
COS: 0.99
Hz: 60
RPM: 3450

I also noted that both caps are 80uF (Ducati, cool!). When I took off the wiring cover I discovered they are connected in parallel so it's not a start+run configuration, it's actually 160uF start only. 

Ducati energia
416.25.A4
80uF +/-5%
400V~10000h / cl. B
450V~  3000h / cl. C
370Vac 50-60Hz


They appear to be spec'd & installed by the motor manufacturer so that adds a wrinkle, wonder who botched it...  I'll see what WM says later today.

[Magicman]

this didn't surprise me as my mill is on a very long run from the service entrance but given the 120A draw it's not too shocking. More info is needed

Your service entrance needs to be addressed before you can make any valid tests or troubleshooting.

[crmorse]

this didn't surprise me as my mill is on a very long run from the service entrance but given the 120A draw it's not too shocking. More info is needed

Your service entrance needs to be addressed before you can make any valid tests or troubleshooting.

This is a very good question. Is the excess current draw being caused by my voltage drop or is the voltage drop happening because of the high current draw?  Which is the cause? I don't know.  I'm highly suspicious of the start capacitor size so I'm leaning that way.  The fact that I'm seeing very little voltage drop (<8v) even at 33A draw gives me a little more confidence in my source but I'm open to any possibilities.
But my mill is where it is, I can't move it closer to the service entrance so if it turns out that startup is right then I'll have to address the problem via other means.
I did speak to WM today and they are researching my question and will get back to me.

[Billmaz]

I have LT15 wide with a 10 hp electric on it works great even if i start the motor with the clutch engaged. I would agree with Southside and say it's a voltage/feed issue. 6 gauge copper should be overkill for that motor.
I wouldn't give up on the electric option, as it's very handy! I love how much quieter it is plus very minimal maintenance!

You have a clutch?! That's exactly what this needs! It starts perfectly with belts off. If it had a clutch I could engage it after startup 

[Billmaz]

I'd be tempted to bring the mill right over next to the power supply and try a very short run of two or four gauge wire, just as a test, to see how it runs. Rule out voltage drop wire problem maybe.

I did that. Disconnected my house too so mill was only thing on it. Same problem 

[Old Greenhorn]

I hate to repeat myself and sound like some kind of nut, but it seems fairly clear it is the inrush (heavy start up) current that is tripping the breaker and a time delay to allow that over current should be a huge help in solving this issue. I wonder what someone like @Al_Smith would say about this?

[btulloh]

After that report about the clutch, it just sounds like the startup torque required by the mill is higher than the startup torque supplied by the electric motor.  Not an electrical problem at all.  Seems out of character for the company could make a design mistake like that.  They are too good for that, but things do happen.  Or perhaps this particular mill (and the other one exhibiting this behavior) has some defect that's creating the need for additional torque.  Anyway you slice it, it just doesn't sound like something WM would miss.  And yet . . .  we are here. 

Kind of maddening, but at least it seems to be headed for a resolution.  I'll be looking forward to hearing the end of the story.  "And they lived happily ever after."  

[Al_Smith]

Well first of all you have a 2 pole motor,3450 Rpm .Generally speaking they don't roll a heavy load on start up as easily  a 4 pole 1725 RPM motor .
One old rule of thumb says about 80 microfarad per kw .So that would be 80 times 5.5 which comes out to 440 and you only have 160 .
I've used larger for hard to start motors a few times and never had a problem .Fact the last rotary converter,a 10 HP  I made which course has no load I used a 1500 m/F .That spins it up in a hurry .
All the cap does is cause what appears to be a phase differential which is caused by the lead the cap makes .On single phase that's only about 30 degrees .
Now then rambling on you can run a 3 phase on single phase just like a converter with a start and run cap but it will only produce some where about 60 percent of the power as 3 phase .Figuring  wattage on 3 phase it's voltage times amperage times 1.73 ( the square root of 3 ) so with single phase the 1.73 is not there any more .HP is figured at 746 watts per HP at 100 % power factor .